Your select methods tell Gnus where to find your Maildir, but not which "groups" to subscribe to. See (gnus) Finding the News
, one of the first sections of the Gnus manual:
First of all, you should know that there is a special buffer called
‘*Server*’ that lists all the servers Gnus knows about. You can press
‘^’ from the Group buffer to see it. In the Server buffer, you can
press ‘<RET>’ on a defined server to see all the groups it serves
(subscribed or not!). You can also add or delete servers, edit a
foreign server’s definition, agentize or de-agentize a server, and do
many other neat things. See Server Buffer. See Foreign Groups.
See Agent Basics.
Though it's possible to subscribe to groups from the Group buffer, I find it easier to go through the Server buffer as described above.
So, from the Group buffer (the one that you're greeted by when you start Gnus) press ^ to get to the Server buffer. Once there, select the relevant Maildir server by pressing RET with point on it. Then you can subscribe to any number of groups by pressing u with point on them. See (gnus) Browse Foreign Server
:
‘u’
Unsubscribe to the current group, or, as will be the case here,
subscribe to it (‘gnus-browse-unsubscribe-current-group’). You can
affect the way the new group is entered into the Group buffer using
the variable ‘gnus-browse-subscribe-newsgroup-method’. See *note
Subscription Methods for available options.
Pressing q twice will exit the group browsing and Server buffers and you should be back in the Group buffer with your new group subscriptions visible.